Covalent Organic Framework-Incorporated Nanofibrous Membrane as an Intelligent Platform for Wound Dressing.

Covalent organic frameworks (COFs) possess fascinating features that have sparked increasing interest as drug carriers in biomedical applications. However, the promising properties of COFs in wound healing have rarely been reported. Herein, a facile one-pot method is reported to prepare a curcumin-loaded COF (CUR@COF) by the condensation reaction and the Schiff base reaction and to further incorporate CUR@COF into polycaprolactone (PCL) nanofibrous membranes (CUR@COF/PCL NFMs) through electrospinning to develop a pH-triggered drug release platform for wound dressing. CUR@COF has a high CUR loading capacity of 27.68%, and CUR@COF/PCL NFMs exhibit increased thermal stability, improved mechanical properties, good biocompatibility, and enhanced antibacterial and antioxidant activities. More importantly, CUR@COF-based membranes show a pH-responsive CUR release profile by protonation under acidic conditions, suggesting the promotion of CUR release from membranes under an acidic extracellular microenvironment. The histopathological analysis and immunofluorescence staining of an in vivo skin defect model indicate that CUR@COF/PCL NFMs can accelerate wound healing and skin regeneration by reducing the expression of inflammatory factors (TNF-α) and enhancing the expression of angiogenesis (VEGF). This work provides a new strategy by employing COF-based drug-encapsulated nanocomposites for wound dressing applications.